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APPARATUS FOR MAKING GAS.

- APPLICATION FILED FEB. 23. 1918.

1 3 6 825 Patented Aug. 9, 1921.

3 SHEETS-SHEET I.

W. D. WILCOX.

APPARATUS FOR MAKING GAS.

APPLICATION FILED FEB. 23, ms.

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APPARATUS FOR MAKING GAS.

APPLICATION FILED FEB. 23. 1918.

1,386,825. Patented 9, 1921.

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WILLKAJVI I). WILGOX, OF CHICAGO, ILLiNOIS.

nrr annrns ron MAKING- ens.

Specification of Letters Patent.

Patented Aug. 9, 1921.

Application filed February 23, 1918. Serial No. 218,799.

T 0 all whom it may concern:

Be it known that I, VVILLIADI D. WILooX, a citizen of the United States, and a resident of Chicago, in the county of Cook and State of Illinois, have invented a certain new and ImprovedApparatus for Making Gas of which the following is a specifica tion, reference being had to the accompanyin drawings.

lily invention relates to the manufacture of gas for domestic and other uses, and has to do particularly with the manufacture of a combined coal and water-gas. The object of my invention is to providea new and improved apparatus, by which gas suitable for domestic and other uses may be produced, and'which will be well adapted ii'or comparatively small installations as well as for those of greater capacity. proved apparatus provides for the utilization of the blast gases produced during the blast period of water-gas.production in the extraneous heating of coal in a separate cok, ing chamber, and at the same time passing the water gas through such coal, thereby economically producing a combined coal and water-gas. It also utilizes the sensible heat of such blast gases in the production of steam to be used during the subsequent run period, thereby further conserving the heat derived from the combustion of the blast gases. in its best embodiment my improved apparatus provides for the production of water-gas simultaneously with the combustion of the blastgases and the incidental extraneous-heating of the coal in the coking chamberby the combustion of the blast gases and the direct heating of such coal by the passage therethrough of the hot watergas, thus securing the greatest economy of heat and time, together with-a continuous production of the combined coal and watergas.

In the accompanying drawings,

Figure l is an end elevation, showing the generators and the lower portion of the coln ing chamber;

F ig. is a partial horizontal section on line 22 of Fig.5.; a

Fig. 3 is a longitudinal vertical section substantially on line 3-3, of Fig, 4;

Fig. d is a'horizontal section on line 4- of Fig. 3;v i

5 is vertical cross-section on line 55 of Fig. 3, and 1 My im- Fig. 6 is a vertical cross-section on line. 66 of Fig. 3.

Referr ng to the drawings,

78 indicate the side walls of the appa- V ratus and 9-10 the end walls thereof. 1l12 lndicate two similar vertical generating chambers which are provided at one. end of the apparatus, and are separated by a partitlon wall 13, as shown in Figs. l and 6. Said generating chambers are provided near their lower ends withgrates 14.15, below which are ash pits 1617, as shown in 1g. 6. 18-19 indicate doors closing openings into said ash pits through which ashes may be removed, and 20-21 indicate doors which close openings into. said generators immediately over the grates 1 l15 therein for the removal of clinkers, etc. 22-23 indicate openings at the upper ends of said generating chambers, through which the fuel, such as coal or a mixture of coal and coke is introduced, said openings being. closed by gas tight doors 2l25, as shown in F ig. 6.

26 indicates a boiler which is set between the side walls 78 atthe opposite end of the apparatus from the generating chainbers l1-12, as shown in Figs. 3 and 4:. 27 indicates a coking chamber placed between the generating chambers 11-.12 and. the boiler 26, as shown in Fig. 4C, and 2829 indicate two secondary combustionchambers, preferably in the form of checker-brick containing chambers also placed between the generating chambers 1l12 and the boiler 26, said checker-brick chambers being at opposite sides of the coking chamber 27, as illustrated inFig. l. 30 indicates a passage leading from the upper portion of the generating chamber 11 to the checker-brick chamber 28, and 31 indicates a similar pas.- sage connecting the upper portion of the chamber 12 with the checker-brick. chamber 29. 32 indicates a passage connecting the lower portion oi the checker-brick cham-. ber 28-with a chamber 33 belowthe boiler- 26 and 34 indicates a similar passage con-- necting the lower portion of the checkerbrick chamber 29 with the chamber The passages 3234 are indicated by dotted lines in Fig. 4, and the passage 34 is shown in full lines in Fig. 3. These passages are provided, respectively, with valves 35.-36 by means of which they may be opened and closed. The purpose of these valves'is to and control the flow of gas from the checkerbrick chambers 2829 to the boiler 26, and any suitable form of valve by which that may be accomplished may be employed. In Fig. 4 I have shown hand-wheels, 3738 for operating said valves.

As best shown in Figs. 3 and 4-, the checker-brick in the chambers 28-29 does not completely fill them, there being unoccupied spaces 39-i0 at the ends of said chambers adjacent to the generating chainbers, which spaces serve as distributing passages to permit the gases entering said chambers from the generating chambers to be distributed throughout the checkenbri'ck chambers, respectively, Similarly, passages 41-42 are provided at the opposite ends of said checker-brick chambers to facilitate the flow of gases at these ends. indicate steam pipes which connect with the lower portions of the passages 41-42, and are also connected with the boiler 26 so that steam from the. boiler may be discharged into the ends of the checker brick chambers 28-29 adjacent to the boiler. Said pipes are provided with valves 45 -46 for controlling the admission of steam to the checker-brick chambers. t. l8 indicate passages leading from the ash pits 1617, respectively, to thecoking chamber, said'passages being controlled by valves Q9 50 shown in Figs. 3 and 6. I

The construction of the coking chamber 27 is best shown in Figs. i and 5. It will be noted that the side walls of such chamber are inclined so that said chamber gradually increases in width from the top downward, thus facilitating the downward passage of the fuel. That portion of the coking cham} ber which lies between the checkerbrick chambers 2829 is provided with inner walls 51 of steel or any other suitable material backed with a comparatively thin brick wall 52, thus permitting the heat of the checker-brick chamber to be communicated to a certain extent to the fuel in the coking chamber. The steel inner lining 51 prevents leakage of gas through the brick portion of the dividing wall between the coking chamher and the checker-brick filled chambers on each side thereof. Said lining may readily closed by a swinging gate 57 having a. latch 58 or other suitable meansfor holding it in its closed position. 59 indicates a water pipe connected with the lower portion of the coking chamber, as shown in Fig. 5. 60 indicates an air pipe which connects with the lower portion of the chamber 55, and is adapted to receive air from a pump 61 of any suitable description. 62 indicates a pipe leading from the upper portion of the chamber 55, at the side opposite that with which the pipe 60 connects, to a vertical pipe 63 shown in Figs. 1 and 3, which is mounted at the end of the apparatus adjacent to the generating chambers 1ll2, and preferably lies midway between said chambers, as shown in Fig. 1. Branch pipes 64-435 controlled by valves 6667, respectively, lead from the pipe 68 to the lower portions of the generating chambers 1112, respectively, below the grates therein, as shown in Fig. 3. Similar branch pipes 6869 controlled by valves 707 1, respectively,lead from theupper end of the pipe 63 to the upper portions of the generating chambers 1112,'respectively, as shown in Figs. 1 and 4c.

72 indicates a gas pipe which leads from the upper portion of the coking chamber 27 to a receiving tank or hydraulic seal pot 73 which may be placed in any suitable location, but for convenience of desciption is here illustrated as being above one of the checker-brick chambers. The tank 73 is adapted-to contain water, as shown in Fig. 5, and is, provided with an overflow pipe 74. 75. indicates a gas outlet pipe leading from the upper portion of the tank 7 3Q 76 indicates a coal reservoir for facilitating the introduction of fuel into the upper portion of the coking chamber 26, said reservoir having a gas tight cover 77. 7 87 9 indicate man-hole covers which cover man-holes through which access may be had from above to the checker-brick chambers.

lt willbe noted that the apparatus described comprises two similar generators each having its own checker-brick chamber, anda single coking chamber arranged to cooperate with said generators In practice the blast and run periods of thetwo generators alternateso'that the continuous production of gas is provided for, the operation. being as follows: When the generator 12 is on blast and the generator 11 on run, the valve 50 which controls the passage etSwhich leads from the ash pit of generator 12 to the coking chamber, is closed and the corresponding valve of the generator 11 is open; also the valve 36 in the passage 34. leading from the checker-brick chamber 29 to the space below the boiler is open and the corresponding valve 35 is closed. The valve 46 in the steam pipe 44 is also closed and the corresponding valve 45 in the steam pipe as is open. At this time the valve 67 which controls the admission of primary air through pipe to the generator 12 below the ate-bars therein, and the valve 71 con trolling the admission of secondary air through pipe 69 to the upper portion of said generator, are open and the corresponding valves 6670 are closed. The pump 61is also in operation to force air under pressure through the chamber 55 at the lower end of the coking chamber, and thence through pipe 62 to the air pipe 63. Bearing these conditions in mind, it willbe apparentthat primary air entering ash pit 17 will rise through the grate-bars 15 and will pass up through the fuel in the generator 12. Owing to the fact that the air so supplied to the generator 12 comes from the chamber 55 surrounding the lower end of the coking chamber it will be hot. The upward passage of the primary air through the fuel in the generator 12 promotes combustion of such fuel, the gases liberated .rising to the upper part of said generator where they become intermixed with secondary air which insures their complete combustion. The burning gasespass from the upper portion of the generating chamber 12 through the passage 31 into the space 40' of checkerbrick chamber 29, from which space they are distributed to the spaces between the checker-brick in said chamber untilQultimately they reach the space 42 at the opposite endof said checker-brick chamber, and thence; pass out through passage 84 into the space below the boiler 26. During their passage through the checker-brick chamber, they highly heat the checker-brick therein, giving up thereto a considerable part of their heat, but when they reach the boiler they are still hot enough to heat the water therein to a high temperature, forming steam.

After. passing through the boiler, the gases escape through a suitable outlet, such as a stack 80 shownin Fig. 3. a I

During the same period of time the generator 11 may be operating on run as above suggested, in which case steam from the boiler is admitted through pipe 43 to the space 41 of checker-brick chamber 28, the checker-brick of which will have been heated to a high temperature. duringthe previous blast period of the generator 11. Consequently, the steam becomes highly superheated by its contact with the hot checkerbrick, and in thatcondition enters the upper end of the generator 11 through passage 80. It then passesdown through the body of incandescent fuel in said generator, by the heat of which it is decomposed'with the formation of hydrogen and carbon monoXid. The water-gasthus produced passes into the ash pit .17 and through passage 47 into an intermediate zone of the coking chamber. For the purpose of laterally dis tributing the water-gas entering the coking chamber so that it will rise uniformly sure of formation, backed up by the steam pressure behind them, rise through the coal the coking chamber, liberating the gases held by the coal, and the combined gases pass out through outlet pipe 72 to the well 73, and may be purified and subjected to such further treatment as may be desired. The liberation of the gases carried by the coal is promoted by heat disseminated through the walls of the upper portion of the coking chamber from the checker-brick chambers, and the downward movement of the coal in the coking chamber is promoted by the widening out ofsaid walls, as has been explained. Coal is admitted from time to time from the fuel reservoir 76 into the upper portion of the coking chamber, and the finished coke is removed at intervals from the lower 'end "of the coking chamber through the gate 57, in .practice coal being admitted and coke being removed during alternating periods. During the downward passage of the coke in the lower portion 27 of the coking chamber it gives up considerable part of its heat to the air which is caused to flow through the chamber 55 under the pressure of, the fan or pump 61, so that such air is heated and the coke when discharged is materially cooled. The downward movement of the coke in the coking chamber is further aided by the inclined sides of the coking chamber. The air heated in the chamber 55 as described, is conducted to the pipe 63 which supplies air to the pri mary and secondary air outlets of the generators, as has already been explained.

After each removal of coke, water is admitted to the lower end of the coking chamber through the pipe 59, which may be provided with a valve 811 for that purpose, a suflicient quantity of water being admitted to provide a water seal to prevent any escape of gas through the gate 57. This water coming into contact with the coke in the lower portion of the coking chamber, quenches it, and is converted into steam which passes up through the fuel body in the coking chamber under the pressure of its formation, resisting by its upward flow any downward passage of water-gas entering the coking chamber through either of the passages 474-8. It also absorbs heat from the coke, which it may, in some degree, impart to the freshly charged coal in the upper part of the coking chamber, thus performing the function, of transferring heat upward in addition to the functions of preventing the escape of combustible gases through the gate 57 and quenching the coke, as has been described. During the time when coke is being removed from the coking chamber, the valve 49 or 50 of the generator on run is closed, (the corresponding valve of the other generator is already closed during that period, as has been .eX- plained), and is allowed to remain closed until the water seal has been formed as.

above described. The steam formed by the quenching of the coke has enough pressure to overcome the gas being evolved in the upper portion of the coking chamber, and therefore, prevents the escape of gases from the upper portion of the coking chamber through the opening at the lower end apparatus described the following beneficial results, among others, are realized:

1. The coal charged into the coking chamber is coked and its volatiles distilled offin part by the heat produced by the second-v ary combustion of the blast gases passing inward through the walls which separate the coking chamber from the checker-brick chamber, and in part by the heat in the water-gas coming into direct contact with it. Both of these heats are in a great degree by-products or waste heat in theproduction of a straight water-gas.

2. The residue of heat in the blastgases is usefully employed in making the steam needed in the generators for the production of water-gas, and the steam passing as it does through the checker-brick chambers before entering the generators is highly superheated so that its decomposition and the formation of hydrogen and carbon monoXid takes place more quickly and with less draft upon the heat in the generator fuel. Moreover, a continuous supply of heat to the steam boiler is provided.

3. The checker-brick acts as a species of heat reservoir so that there is less variation in the temperature in the checkerbrick chambers in the interval between blast and run periods than would otherwise be the case. r

4;. One or the other of the generators being substantially at all times producing water-gas, there is a continuous current of hot water-gas passing into the material in the coking chamber.

5. By frequent additions of fresh coal to is removed at the bottom, and consequentlyeach of such charges is subjected to the same conditions as regardsheating as every other charge, thereby insuring a fairly uniform product. 7

7. The passage of the residue formed in.

the coking chamber through the compara tively cool'lower portion of said chamber serves to extract from it after it has been substantially coked a large part of its sensible heat, and with the cooling effect of the turning into steam of the water admitted to the lower portion of the coking chamber and of'thesuperhe'ating of such steam by contact with the coke in passing upward, the residue in the bottom of the coking chamber is quenched and cooled prior to its removal. The steam in the lower portion of the body of the coke prevents any downward passage of wateras and its escape into the air when the lower end of the coking chamber-is opened for the removal of less of the heat of combustion in attaining I the temperature necessary for combustion.

9. By grouping the several parts of the apparatus in the manner described, the

amount of heat lost through radiation is materially reduced, thereby economizing in the cost of operation. 7

. In the use of the apparatus thus far described, it mayoccur that the coal in the coking chamber, and particularly that portion which occupies the space therein farthestfremo'ved from'the heated walls thereof, will not be heated to the degree necese sary. or desired for the production of coke or the fairly complete removal therefrom of its volatile elements, and my invention, therefore, contemplates the provision of means by which superheated water gas may be passed into the coking. chamber, thereby raising the temperature to which the fuel to be carbonized will be brought. For this purpose I provide steam pipes 8283 which discharge into the ash pits l617 adjacent to the grate bars 1415; said steam pipes are supplied with steam from the boiler 26, or any other suitable source, and are provided with valves 8%-85, respectively, by which the flow of steam therethrough may be controlled. 86-87 indicate gate valves in openings leading from the lower portions of the passages 4142 to the passages 47-48, as shown in Figs. 3 and 5. It will be apparent that by closing the valves 49-50 and opening the valves 8'6 8T, steam admitted through the pipes '8283 may be caused to flow upward through the generating chambers, thence through the checker brick chambers and down into the passages 4:74i8, which as has been explained, discharge'into the coking chamber 27.v In practice, at the conclusion of the blast periodof either generator, the gate valve 86 or 87, as the case may be, controlling the passage of the waste gases from the appropriate checker brick chamber to the boiler would not be at once closed, but a short period of time would be allowed to elapse following the shutting off of the secondary air during which steam' would be admitted through the appropriate pipe 82 or 83'to the ash pit of that generator. The steam so admitted would rise through the fuel in the generator, with the production of water gas, which would flow through the checker brick chamber, purging the fuel body of the combustion products and also the open space above the fuel and the checker brick chamber connected therewith. The appropriate gate valve 37 or 38 would then be closed and the gate valve 86 01"87 opened, permitting the water gas, which would then be highly superheated bycontact with the checker brick chamber, to escape into the passage 47 or 4:8 and thence into'the fuel in the coking chamber. In this mode of operation a larger proportion of the fuel in the generating chamber will be consumed in supplying heat to the checker brick chamber, the total volume of water gas per unit of generator fuel will be less, but the total number of heat units passed into the-coking chamber will be increased, and the fuel to be carbonized will be brought" to a higher temperature, as stated above. If desired also this mode of operation could be alternated with that previously described, mak ing a down run through the generating chamber during one cycle and an up run during the succeeding cycle, a practice which aids in preserving good conditions in the fuel bed therein.

The apparatus described may be modified in many respects without departing from the invention set forth in the generic claims hereinafter made, and I wish it to be understood that my invention includes such" changes or modifications as'would occur to those skilled in the art.

What I claim as my invention, and desire to secure by Letters Patent, is

1. A-gas making apparatus comprising a generator, a secondary combustion chamber communicating with the upper portion of said generator, a separate coking chamber adjacent to'said secondary combustion chamber and adapted to be heated therefrom, means for admitting steam into said secondary combustion-chamber, a duct connecting the lower portion of said generator with said] coking chamber, and controlling devices for controlling the flow of gases through theapparatus, whereby blast gases from the generator maybe caused to flow through said secondary combustion chamber, and gases formed in said secondary combustion chamber may be caused to flow into the upper portion of the generator and thence down ward through the material therein to said coking chamber.

2.;A gas making apparatus comprising a generator, a secondary combustion chamber communicating with the upper portion of said generator, a separate coking chamber adjacent to said secondary cornbustioi'i chamber and adapted to be heated tlhQl'G. from, means for admitting steam into said" secondary combustion chamber, a duct connecting the lower portion'of sa-idgenerator with said coking chamber, -::ontrolling'devices for controlling the how of gases through the apparatus, whereby blast gases from the generator may be caused to flow through said secondary combustion cham-- ber, and steam superheated in said second-' ary combustion chamber may be caused to flow into the upper portion of the generator and thence downward through the material therein to said coking chambenand means for admitting air into the upper portion of said generator. 7 3. A gas making apparatus comprising a generator, a. secondary combustion chamber communicating at one end portion thereof with the upper portion or said generator, a boiler connected with the opposite end portion of said-secondarycombustion chamberand heated by blast ases therefrom, a steam to pipe leading from the boiler to the latter end portion of said secondary combustion cham ber, and controlling devices for controlling the flow of gases in one direction or the other, from said generator through said secondary combustion chamber, or vice versa.

4. A making apparatus comprising a generator, a secondary combustion chamber communicating at one end portion thereof with the upper portion of said generator, a boiler connected with the opposite end portion of said secondary combustion chamber and heated by blast gases therefrom, steam pipe leading from the boiler to the latter end portion of said secondary combustron chamber, controlling devices for controlhng the flow of gases'in one direction. or the other,- from said generator through, said secondary nected therewith combustion chamber, or vice versa, a coking chamber adjacent to and heated by said secondary combustion chamber, and means for conducting gases flowing from said secondary combustion chamber down through said generator to said coking chamber.

5. A gas making apparatus comprising a generator, a secondary combustion chamber communicating with the upper portion of said generator, a. coking chamber adjacent to said secondary combustion chamber and arranged to be heated therefrom,a duct con-,,

necting the lower portion of the generator with the coking chamber, means associated with the coking chamber for heatin air, means for supplying 'air heated by the coke in said coking chamber to said generator,

and controlling devices for causing gases to flow from said generator through said secdevices for controlling the flow of the gases, 7

whereby gases may be caused to flow from one of said generators through the secondary combustion chamber connected therewith and simultaneously steam may be caused to flow through the other secondary combustion chamber into the generator conand thence downward through said generator into said coking chamber, and vice versa. 7

7. A continuous gas producing apparatus comprising a plurality of generators, secondary combustion chambers communicating with the upper portions of said generators, a separate coking chamber associated with and heated by said secondary combustion chambers and connected with the lower portions of said generators, means for admitting steam to said secondary combustion chambers, and controlling devices for controlling the flow of the gases, whereby gases may be caused to flow from one of said generators through the secondary. combustion chamber connected therewith and simultaneously steam may be caused to flow throughthe other secondary combustion chamber into the generator connected therewith and thence downward through said generator into said coking chamber, and vice versa.

8. A continuous gas producing apparatus comprising "a plurality of generators, secondary combustion chambers communicat ing with the upper portions of saidgenerators, a coking chamber connected with the lower portions of said generators, means for admitting steam to sald secondary combustion chambers, controlhng devlces for con trolling the flow of the gases, whereby gases may be caused to flow from one of said gen erators through the checker-brick chamber.

connected therewith and simultaneously steam may be caused to flow through the other checker-brick chamber into the gener ator connected therewith and thence down ward through said generator into said coking chamber, and vice versa, and means for supplying said generators with air heated by the coke in said coking chamber.

9.. A gas making apparatus comprising a coking chamber hrving an opening 'at' its lower endportion for the discharge of coke therefrom, anair chamber surrounding the lower portion of said coking chamber, a generator communicating with said coking chamber, means for causing gas to flow from said generator into said coking chamber, and means for conducting air from said air chamber into said generator.

10. A gas making apparatus comprising a coking chamber having an opening in its lower end portion for the discharge of coke therefrom, and a gas discharge outlet at its.

upper end portion, means for generating water-gas, and a duct leading from said generating means and communicating intermediately with said coking chamber for introducing water-gas thereinto.

11. A gas making apparatus comprising a coking chamber having an J opening in its I lower end portion for the discharge of coke therefrom, and a gas discharge'outlet at its upper end portion, means for generating water-gas, a duct leading from said generatingmeans and communicating intermediately with said coking chamber for introducing water-gas thereinto, and means for lntroducmg water lnto the lower said coking chamber. 1

12. A gas making apparatus COIHPIISHXg a generator, a secondary; combustion chamber communicating with the upper portion of said generator, a separate coking chamberad acent to said secondary combustion cham her and arranged to be heated therefrom,- means communicating with the lower portion of said generator for-supplying steam thereto, a valve controlled passage between said secondary combustion chamber and the coking chamber for supplying the coking chamberwith gases'passing from the generator through said secondary combustion chamber, means for supplying steam directly to the secondary combustion chamber,

whereby itmay-be caused to pass back therethroughto the generator, and valvecontrolled passages for conducting the gases formed in the latter operation to the coking chamber. i a I portion of the secondary combustion chamber and caused to pass .therethrough into the upper portion of the generator and down therethrough to the coking chamber.

14:. An apparatus for the manufacture of gas comprising two water gas generators, two laterally placed secondary combustion chambers, an opening from the upper part of each generator into the corresponding secondary combustion chamber, a vertical retort placed between the secondary combustion chambers, closable opening from.

each secondary combustion chamber into the lower portion of the retort, means for supplying air to the upper and lower portions of each generator, and means for admitting steam to the lower portion of each generator.

15. An apparatus for the manufacture of gas comprising two water gas generators, two laterally placed secondary combustion chambers, an opening from the upper part of each generator into the corresponding secondary combustion chamber, a vertical retort placed between the secondary combustion chambers, a closable outlet for waste gases from each secondary combustion chamber, means for admitting steam to each secondary combustion chamber, a closable opening from the lower portion of each generator into the lower portion of the vertical retort, and means for supplying air to the upper and lower portions of each generator.

16. An apparatus for the manufacture of gas comprising two water gas generators, two adjacent secondary combustion chambers, an opening from the upper part of each generator into the corresponding secondary combustion chamber, a vertical retort placed between the combustion chambers, a'closable outlet for waste gases in each secondary combustion chamber, closable openings from each secondary combustion chamber into the lower portion of the vertical retort, closable openings from the lower portion of each generator into the lower portion of the vertical retort, means for admitting steam to each secondary combustion chamber, means for admitting steam to the lower portion of each generator, and means for supplying air to the upper and lower portion of each generator.

17. An apparatus for the manufacture of gas comprising a plurality of water gas generators, a corresponding plurality of secondary combustion chambers, an opening from the upper portion of each generator into the corresponding secondary combustion chamber, a vertical retort substantially inclosed by the secondary combustion chambers, a closable outlet for waste gases from each secondary combustion chamber, a closable opening from each secondary combustion chamber into the lower portion of theretort, means for supplying air to the upper and lower portions'of each generator, and means for admitting steam to the lower portion of each generator.

18. An apparatus for the manufacture of gas comprising a plurality of water gas generators, a corresponding plurality of secondary combustion chambers, an opening from the upper portion of each generator into the corresponding secondary combustion chamber, a vertical retort substantially inclosed by the secondary combustion cham bers, a closable outlet for waste gases from each secondary combustion chamber, means for admitting steam to each secondary combustion chamber, a closable opening from the lower portion of each generator into the lowerportion of the vertical retort, and means for supplying air to the upper and lower portions of each generator.

19. An apparatus for the manufacture of gas comprising a plurality of water gas generators, a corresponding plurality of secondary combustion chambers, an opening from the upper portion of each generator into the corresponding secondary combustion chamber, a vertical retort substantially inclosed by the secondary combustion chambers, a closablev outlet for waste gases in each secondary combustion chambe closable openings from each secondary combustion chamber into the lower portion of the vertical retort, closable openings from the lower portion of each generator into the lower portion of the vertical retort, means for admitting steam to each secondary combustion chamber, means for admitting steam to the lower portion of each generator, and means for supplying air to the upper and lower portions of each generator.

WILLIAM D. WILCOX. 

